364 CULTIVATED VEGETABLES. 



gated ; but this does not disprove their being 

 produced likewise by putrefaction, of which 

 we have continual instances, and in situations 

 where mushroom seed or dust could not 

 reach. The embryo plants are discovered 

 under the form of a white mouldy, fibrous 

 substance, called spawn, and which is caused 

 by certain particles in particular kinds of 

 dung being excluded from light and air. 

 The mouldiness on stale wine or beer, as also 

 on bread and other moist substances, as well 

 as on liquids kept in an open vessel that is ex- 

 cluded from free air, appears like mushrooms, 

 when viewed through a microscope. The 

 dust of this mould will communicate itself 

 rapidly to other substances within its reach \ 

 thus appearing, like the mushroom, to owe 

 its origin both to seed and to putrefaction. 



In 1729, Micheli first announced his dis- 

 covery, that different kinds of mushrooms 

 had flowers and seeds ; and this having been 

 confirmed in 1753 by M. Gleditsch, and in 

 1755 by M. Battarra, they have therefore 

 divided them into two classes, one of which 

 they suppose to have only seed, the other 

 both flowers and seed. The author has never 

 been able to discover what to him would 

 satisfactorily prove the flowers of this curious 



